Title: A simple method for study of effect of Kerr nonlinearity on effective core area, index of refraction and fractional modal power through the core of monomode graded index fibre
Authors: Mithun Maity; Anup Kumar Maiti; Himadri Mandal; Sankar Gangopadhyay
Addresses: Department of Electronics, Brainware University, Barasat, Kolkata, 700125, India ' Department of Electronics, Brainware University, Barasat, Kolkata, 700125, India ' Department of Electronics and Communication Engineering, Calcutta Institute of Technology, Uluberia, Howrah, 711316, India ' Department of Electronics, Brainware University, Barasat, Kolkata, 700125, India
Abstract: Using the simple power series expression for fundamental modal field derived by Chebyshev technique, we present investigation of some important propagation parameters like effective core area, index of refraction and fractional modal power guided through the core of single-mode graded index fibre in presence of Kerr nonlinearity. In absence of nonlinearity, the said power series expression leads to prescription of analytical expressions of the concerned propagation parameters. Employing those analytical expressions, we apply iterative method in order to evaluate the said parameters in presence of Kerr nonlinearity. Choosing some typical single-mode step and parabolic index fibres for our study, we verify that the results obtained by our simple formalism match excellently with the exact results which are obtainable by applying rigorous finite element technique. This excellent agreement attests to the accuracy of our formalism. Further, our formalism requires little computation in the context of evaluation of the said parameters. Accordingly, our formalism can be considered as a simple but accurate alternative to the existing complicated methods available in literature. Thus, this user-friendly but accurate formalism will benefit the system engineers in respect of selection of suitable fibre in which modal noise due to nonlinearity is minimum.
Keywords: graded index fibre; cladding decay parameter; V number; effective core area; index of refraction; confinement of modal power; Kerr nonlinearity; Chebyshev technique.
International Journal of Nanoparticles, 2020 Vol.12 No.1/2, pp.136 - 151
Received: 15 Jan 2019
Accepted: 10 Jul 2019
Published online: 24 Mar 2020 *